Skip to main content

Full text of "The manufacture and properties of iron and steel"

See other formats


INFLUENCE OP CERTAIN" ELEMENTS ON STEEL.
367
.seen in the softest products of the basic open-hearth and in the purest of acid steel. On the contrary, it is well known that the reverse is true, and that the ductility increases as the condition of pure iron is approached.
TABLE XVII-M. Data on Very Soft Basic Open-Hearth Steel.
	.								
	ri				a			a	
'eat number.	arbon by combustion; per ceJ	arbon by color; per cent.	hosphorus ; per cent.	anganese; per cent.	alphur; percen	opper; percent	lastic limit; pounds per square inch.	Itimate strengl pounds per square inch.	lastio ratio; per cent.
R	Q	O	fM	3	02	O	W	P	W
4060		.04	.007	.02	.024	.10	28420	45620	62.8
4800		.04	.007	.05	.010	.05	80640	40310	66.2
4030		.04	.007	.04	.021	.06	24870	46000	53.0
4032		.04	.011	.04	.029	.04	25810	46480	55.5
4971		.08	.010	.05	-.OS2	.14	20780	47140	56.8
4072		.04	.010	.04	A021	.10	27020	47000	50.4
Average,	.025	.04	.009	.04	.024	.08	27323	46425	68.9
In a discussion of a paper by Webster, II. D. Hibbard* deduced the fact that oxide of iron reduces the tensile strength.of very soft metal by several thousand pounds. I cannot indorse this conclusion, but offer Table XVII-M as evidence to the contrary. These heats were made in a basic open-hearth furnace, and their regularity shows that we are dealing with a normal and definite metal and not with an accidental product. They were purposely made with the lowest possible content of manganese, and it seems certain that the steel must be saturated with oxygen. These steels are much stronger than would be expected as compared with those containing more carbon. It may be that the first increments of carbon have less strengthening effect than further additions, or it may be that the first increments of manganese have a marked weakening effect, but it is more probable that the oxide of iron increases the ultimate strength.
* Trans. A. I. M. E.t VoL XXI, p. 998